Abstract: A method of dehydrating a solvent originating from a hydrocarbon dewaxing operation, wherein a moist composite organic solvent, for example a moist MEK/toluene mixture is dehydrated in a first distillation zone, the resulting first distillate is contacted with water to form two phases one of which, rich in organic solvent, is returned as a reflux to the first distillation zone whereas the other phase rich in water is distilled in a second distillation zone, and the head product and one portion of the bottom product of the second distillation zone are returned to the zone of contact between the first distillate and water, the invention being applicable to the dewaxing of lubricating oils.

Abstract: A tubular pressurized catalytic hydrocarbon converter provided with a cylindrical casing (1) containing vertical gas exhaust pipes (4) around which are arranged reaction tubes (2) which are coaxially placed in sleeves (3). The lower portions of these tubes are connected to the vertical pipes by "pig-tails" and have a novel design since the aim is to increase the converter's reliability and working life by eliminating reaction tube deformation and facilitating "pig-tail" assembly and maintenance. To this end, the converter is provided with a transverse wall attached to the lower ends of the sleeves and provided with openings in which the lower ends of the tubes and vertical pipes are freely inserted. It is also provided with plates (7) having movable covers (8) and attached to the lower ends of the vertical pipes which are in turn connected to the "pig-tails".

Abstract: A method of liquefying natural gas, wherein the gas (1) is cooled and separated into a liquid phase (6) and a gaseous phase (8) which is expanded (9) and added to the liquid phase in the column (7), at the head of which the gas enriched with methane (21) is separated and recompressed (27) and carried to the liquefaction (32, 33, 34) whereas the liquid phase from the bottom of column (7) is expanded and rectified in column (14); the head effluent (19) being condensed (20) and conveyed as a reflux (25) to column (7); the pressure in column (7) being higher than that of column (14); the C.sub.3 + hydrocarbons from the bottom (16) being separated and the methane liquefaction (33, 34) being conventional.

Abstract: A method of and a plant for recovering liquid hydrocarbons in a gaseous batch, the plant comprising a compressor for the gaseous batch, a column for absorbing C5 and heavier hydrocarbons associated with a debutanization column; a column for absorbing C3 and heavier hydrocarbons associated with a de-ethanization column and with a heat exchange system connected to a refrigeration cycle, the plant providing from a gaseous batch issuing from a catalytic cracking unit a debutanized gasoline, a liquefied gas cut (C3 and C4-hydrocarbons) and a gaseous cut (C2 and lighter hydrocarbons) wherein the losses of C3 and higher C-hydrocarbons are much smaller than that occurring with existing plants.

Abstract: A method of and system for recovering a solvent from a mixture of solvent and hydrocarbons, the system comprising at least two evaporation flasks successively fed with a charge consisting of said mixture to be separated, at least one steam generator performing the condensation of the solvent, a circuit for conveying the evaporated solvent and connecting the flasks to the generator and a circuit of an intermediate fluid in gaseous phase including a compressor for raising the condensation temperature of this fluid, the latter circuit connecting the generator to heat exchangers arranged upstream of each flask.

Abstract: The invention relates to a method and an apparatus for cryogenic fractionation of a gaseous feed comprising a contact purifying-refrigerating column into the bottom of which is injected a partially condensed gaseous feed, the said column producing in its head portion a residual gas and in its bottom portion a liquid which is injected into a fractionating column producing in its head portion a distillate which is at least partially condensed and injected into the head portion of the column to thus recover in the bottom liquid of this column the heavy compounds contained in the vaporized fraction of the gaseous feed.

Abstract: The present invention relates to a process and an apparatus for cryogenic fractionation of gas feeds, the apparatus comprising essentially a contact purifying-refrigerating column associated with a fractionating column, an exchange system, a plurality of ducts with valves connecting the above three elements and two closed end independent refrigerating circuits integrated to the exchange system.

Abstract: The present invention relates to a method and an apparatus for liquefying a gas with a low boiling point, such as natural gas, by heat exchange with a main refrigerant fluid having several components. The whole of the vapor phase of this main refrigerant fluid, after being condensed and subcooled, is expanded at once to at least one first pressure, and the whole of the liquid phase of the subcooled main refrigerant fluid is expanded at once to at least one second pressure, different from the said first pressure.

Abstract: A user is assisted in accomplishing a technical operation, such as a graph, or the like, by an interactive computer program having an element movable with respect to another element so as to display, at each step of the program, all the information necessary for its execution.

Abstract: The present invention relates to a method and an apparatus for producing ethylene. This apparatus comprises essentially a phase separator connected to an ethylene fractionating unit. The fractionating unit comprises a first or lower-pressure fractionating column and a second or higher-pressure fractionating column, the second column being fed with an intermediate liquid fraction from the first column and having its head connected to the heating circuit of the reboiling system associated with the first column to at least partially condense the head fraction of the second column. Thus, the invention allows high-purity ethylene to be produced with minimum energy consumption.

Abstract: A method of making ethylene consisting in processing an ethylene gas condensate which is passed through a de-ethanizer to separate as gases the C.sub.2 -hydrocarbons with two carbon atoms, cooling said hydrocarbons to condensate a part thereof, feeding said hydrocarbons into a separator where the condensed phase is separated and recycled to the de-ethanizer, and feeding the non-condensed fraction of said hydrocarbons into an ethylene-recovering unit with which is associated a reboiling system for heating the fluid taken from said unit prior to recycling it to the latter, and further comprising the step of exchanging heat between the hydrocarbons from the de-ethanizer and the reflux fluid from said reboiling system so as to at least partially condensate the hydrocarbons fed to said separator.

Abstract: A process of and apparatus for liquefying a dry gas with low boiling point in a first circuit through heat exchange with a main refrigerating fluid in a second circuit itself pre-cooled to its at least partial liquefaction through heat exchange with an auxiliary refrigerating fluid in a third circuit, wherein, for a same amount of treated products, the required total compression input power for the refrigerating fluids is reduced by performing in said third circuit an intermediate condensation between the two last compression stages followed by a phase separation, the gaseous phase being compressed to a high pressure in the last compression stage whereas the liquid phase is compressed to a high pressure by a pump and recycled to a cryogenic heat exchanger for cooling the gas initially in the moist state thereby at least partially drying same.

Abstract: A process of and an apparatus for saving energy in a method of liquefying a natural gas by cooling same with the vapor from a liquid coolant sub-cooled after expansion thereof in the liquid condition, the vapor simultaneously sub-cooling the liquefied coolant, the process consisting in expanding the sub-cooled high-pressure liquid coolant in a hydraulic turbine providing mechanical power possibly for driving a rotary machine.

Abstract: This invention relates to a method for treating residue gases proceeding from units applying the Claus reaction for the removal of sulphur and having been subjected to a conversion of the sulphur compounds into sulphuretted hydrogen.This method consists in that, prior to absorption of the sulphuretted hydrogen by a selective solvent in aqueous solution, the gases to be treated are cooled to a temperature so selected as to condense the water contained in the gases to form an aqueous effluent which is thereafter injected into the circuit of the selective solvent.

Abstract: A large capacity tank for the seasonal storage of hot water from electrical power-generating thermal and nuclear plants to be used seasonally to heat buildings, consisting of a large basin which comprises partitions dividing the basin into several portions communicating with each other in parallel and/or series relationship, at least one hot water supply input from said plants, leading to the distribution systems which open into one portion of the basin and at least one cold make-up and/or return water supply input for the distribution systems opening into another portion of said basin.

Abstract: Method and apparatus for cooling a gaseous mixture wherein a fractional condensation of said mixture is carried out under a high pressure by using at least a first stage and a last stage of fractional condensation, the penultimate and the last condensed fractions are expanded down to a low pressure forming a main refrigerating stream, and at least the first condensed fraction of the cycle mixture is expanded down to an intermediate pressure between said high pressure and said low pressure forming an auxiliary refrigerating stream.

Abstract: A method of processing through low temperature heat exchanges natural gases and cracked gases consisting in using a cooling cycle including compressing and then cooling a cycle mixture of gases consisting of C1 hydrocarbons, C2 hydrocarbons and C3 hydrocarbons through outer coolers with attendant total liquefaction of the cycle mixture under pressure; subsequently effecting a sub-cooling of the mixture within heat exchanges in counter-current relation to one expanded part thereof and/or cold returns and rejects of products processed in the cycle and finally expanding said sub-cooled mixture in at least one exchanger where various cooling processes of the treated products are carried out at successive temperature levels.

Abstract: 1.

Abstract: .Iadd.17. A process for totally liquefying a gaseous methane-rich feed stream comprising the steps of:a. supplying said methane-rich feed stream at a superatmospheric pressure and precooling said stream,b. providing a multicomponent refrigerant,c. compressing said multicomponent refrigerant to a superatmospheric pressure,d. cooling said multicomponent refrigerant and phase separating a single vapor fraction and a single liquid fraction from said cooled multicomponent refrigerant,e. subcooling said liquid fraction in heat exchange with itself after expansion to form a first subcooled liquid fraction,f. liquefying and subcooling all of said vapor fraction in heat exchange with said first subcooled liquid fraction, and with itself after expansion, to form a second subcooled liquid fraction, andg.

Abstract: .Iadd. .Iadd.8. A method for cooling a second gaseous mixture to low temperature and producing at least one constituent of said mixture in liquid phase, comprising:a. cooling and subjecting first gaseous mixture containing at least one component of said secong gaseous mixture, to a fractionate condensation under a first pressure,b. expanding at least two condensed fractions obtained during the fractionate condensation of said first gaseous mixture, reuniting the expanded condensed fractions with said first gaseous mixture under a second pressure lower than said first pressure, vaporizing and reheating the reunited fractions with said first gaseous mixture under said second pressure, by heat exchange with said second gaseous mixture undergoing cooling, and with said first gaseous mixture undergoing fractionate condensation, and recompressing said first gaseous mixture to said first pressure,c.